Why mosquitoes love us Knowing Neurons

Why Mosquitoes Love Us

From that evil itch on your arm to torturous diseases such as malaria, Zika, dengue, and yellow fever, mosquito bites can have unpleasant consequences. But have you ever wondered why those skin-diving insects are so good at detecting humans? Not so surprisingly, the answer lies in neuroscience — in a special field called chemosensation, the sensing of chemical stimuli.Continue reading

Zebrafish

What Zebrafish Teach Us About Touch

Unlike the sense of vision, which is perceived only by light-sensitive photoreceptors in our eyes, the mechanoreceptors that respond to light touch are located in sensory neurons all over the body.  Our sense of touch starts in the skin, where sensory neurons with elaborate dendrites just below the skin’s surface provide dense coverage over the entire area of the body.  When we touch something, the mechanical pressure created by the contact between an object and our skin opens mechanoreceptors that cause the sensory neuron to fire an action potential and activate downstream neurons.  We are constantly coming into physical contact with objects and people in our environment, and as a result a large number sensory neurons are being activated over many different areas of our body at any given moment!  How does the nervous system handle all of this incoming tactile information?Continue reading

Science with a Touch of Art: A Conversation with David Ginty

David GintyIf you think about it, the surface of the human body, the skin, is actually one huge sheet of tactile receptors. The dozens of types of receptors that innervate the skin help us connect with our surroundings. But the properties of these neurons – how they are organized in the skin, where the project into the spinal cord and brainstem, and how this organization gives rise to the sense of touch – are actually poorly understood! I spoke with David Ginty, Ph.D., who is Professor of Neurobiology at Harvard Medical School and an investigator with the Howard Hughes Medical Institute, to find out about the newest ways his lab is studying sensory biology.Continue reading

A Tale of Two Aphasias

Paul Broca
Paul Broca

It’s 1861, and the French neurologist Paul Broca is examining a new patient. Dr. Broca is puzzled because all the patient can say is “tan.” When Dr. Broca asks him questions, Tan cannot seem to form the words. However, it is clear that Tan can understand language because, when he asked to whistle or sing a melody, he can do so without a problem. Something is wrong with his ability to speak! When he is asked to speak grammatically or create complete sentences, he cannot do it – not even in writing! Dr. Broca doesn’t know what to do for Tan, since he knows that Tan must have brain damage… but where?Continue reading

Hearing is Believing: Cells that Enable Hearing after Birth

The sense of hearing is a critical part of how we experience life and the world around us. It is so important, in fact, that the ears are fully formed and functional when we are born. Despite its significance, hearing is often underappreciated until it is lost. Hearing loss affects more than 10% of all people worldwide. Whether it is due to age, exposure to loud noises, or genetic mutations, hearing loss occurs when hair cells, the receptors in the ears that respond to sound, become damaged and die. One of the biggest challenges in counteracting hearing loss is that hair cells cannot repair or regenerate themselves, so the damage is often permanent.Continue reading

The amygdala: a full brain integrator in the face of fear

You are sitting at your computer quietly reading this article when – BOOM! – there is a sharp loud noise behind you! You instinctively stop what you are doing, jump up, and turn to the source of the noise. You freeze where you stand, and your brain quickly assesses the danger of the situation. Although it may seem like a brief moment, your brain is processing a ton of information and trying to decide if you should run away or stay and fight!Continue reading